"""
Funcs.py

Funcs.py, a member of MiscUtils, holds functions that don't fit in anywhere else.
"""

import md5, os, random, string, time, sys, tempfile
True, False = 1==1, 1==0


def commas(number):
    """ Returns the given number as a string with commas to separate the thousands positions. The number can be a float, int, long or string. Returns None for None. """
    if number is None:
        return None
    if not number:
        return str(number)
    number = list(str(number))
    if '.' in number:
        i = number.index('.')
    else:
        i = len(number)
    while 1:
        i = i-3
        if i<=0 or number[i-1]=='-':
            break
        number[i:i] = [',']
    return string.join(number, '')


def charWrap(s, width, hanging=0):
    """ Returns a new version of the string word wrapped with the given width and hanging indent. The font is assumed to be monospaced.
    This can be useful for including text between <pre> </pre> tags since <pre> will not word wrap and for lengthly lines, will increase the width of a web page.
    It can also be used to help delineate the entries in log-style output by passing hanging=4.
    """
    import string
    if not s:
        return s
    assert hanging<width
    hanging = ' ' * hanging
    lines = string.split(s, '\n')
    i = 0
    while i<len(lines):
        s = lines[i]
        while len(s)>width:
            t = s[width:]
            s = s[:width]
            lines[i] = s
            i = i + 1
            lines.insert(i, None)
            s = hanging + t
        else:
            lines[i] = s
        i = i + 1
    return string.join(lines, '\n')

# Python 2.3 contains mktemp and mkstemp, both of which accept a
# directory argument.  Earlier versions of Python only contained
# mktemp which didn't accept a directory argument.  So we have to
# implement our own versions here.
if sys.version_info >= (2, 3, None, None):
    # Just use the Python 2.3 built-in versions.
    from tempfile import mktemp, mkstemp
else:
    def mktemp(suffix="", dir=None):
        """
        User-callable function to return a unique temporary file name.
        
        Duplicated from Python's own tempfile with the optional "dir"
        argument added. This allows customization of the directory, without
        having to take over the module level variable, tempdir.
        """
        if not dir: dir = tempfile.gettempdir()
        pre = tempfile.gettempprefix()
        while 1:
            i = tempfile._counter.get_next()
            file = os.path.join(dir, pre + str(i) + suffix)
            if not os.path.exists(file):
                return file

    def mkstemp(suffix="", dir=None):
        """
        User-callable function to return a tuple containing:
            - a os-level file handle for the temp file, open for read/write
            - the absolute path of that file

        Note that this version of the function is not as secure as the
        version included in Python 2.3.
        """
        path = mktemp(suffix, dir)
        return os.open(path, os.O_RDWR|os.O_CREAT|os.O_EXCL, 0600), path

def wordWrap(s, width=78):
    """
    Returns a version of the string word wrapped to the given width.
    Respects existing newlines in the string.

    Taken from:
    http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/148061
    """
    return reduce(
        lambda line, word, width=width: "%s%s%s" % (
            line,
            ' \n'[(len(line[line.rfind('\n')+1:]) + len(word) >= width)],
            word
        ),
        s.split(' ')
    )


def dateForEmail(now=None):
    """ Returns a properly formatted date/time string for email messages """
    if now is None:
        now = time.localtime(time.time())
    if now[8]==1:
        offset = -time.altzone / 60
    else:
        offset = -time.timezone / 60
    if offset<0:
        plusminus = '-'
    else:
        plusminus = '+'
    return time.strftime('%a, %d %b %Y %H:%M:%S ', now) + plusminus + '%02d%02d' % (abs(offset/60), abs(offset%60))


def hostName():
    """
    Returns the host name which is taken first from the os environment and failing that, from the 'hostname' executable. May return None if neither attempt succeeded.
    The environment keys checked are HOST and HOSTNAME both upper and lower case.
    """
    for name in ['HOST', 'HOSTNAME', 'host', 'hostname']:
        hostName = os.environ.get(name, None)
        if hostName:
            break
    if not hostName:
        hostName = string.strip(os.popen('hostname').read())
    if not hostName:
        hostName = None
    else:
        hostName = string.lower(hostName)
    return hostName


_localIP = None

def localIP(remote=('www.yahoo.com', 80), useCache=1):
    """
    Gets the "public" address of the local machine, i.e. that address
    which is connected to the general Internet.

    This function connects to a remote HTTP server the first time it is
    invoked (or every time it is invoked with useCache=0). If that is
    not acceptable, pass remote=None, but be warned that the result is
    less likely to be externally visible.

    Getting your local ip is actually quite complex. If this function
    is not serving your needs then you probably need to think deeply
    about what you really want and how your network is really set up.
    Search comp.lang.python for "local ip" for more information.
    http://groups.google.com/groups?q=%22local+ip%22+group:comp.lang.python.*
    """
    global _localIP
    if useCache and _localIP:
        return _localIP
    import socket
    if remote:
        # code from Donn Cave on comp.lang.python

        # My notes:
        # Q: Why not use this?  socket.gethostbyname(socket.gethostname())
        # A: On some machines, it returns '127.0.0.1' - not what we had in mind.
        #
        # Q: Why not use this?  socket.gethostbyname_ex(socket.gethostname())[2]
        # A: Because some machines have more than one IP (think "VPN", etc.) and
        #    there is no easy way to tell which one is the externally visible IP.

        try:
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.connect(remote)
            ip, port = s.getsockname()
            s.close()
            _localIP = ip
            return _localIP
        except socket.error:
            # oh, well. we'll use the local method
            pass

    addresses = socket.gethostbyname_ex(socket.gethostname())[2]
    for address in addresses:
        if address!='127.0.0.1':
            if useCache:
                _localIP = address
            return address
    if useCache:
        _localIP = addresses[0]
    return _localIP


def timestamp(numSecs=None):
    """
    Returns a dictionary whose keys give different versions of the timestamp:
        'numSecs': the number of seconds
        'tuple': (year, month, day, hour, min, sec)
        'pretty': 'YYYY-MM-DD HH:MM:SS'
        'condensed': 'YYYYMMDDHHMMSS'
        'dashed': 'YYYY-MM-DD-HH-MM-SS'
    The focus is on the year, month, day, hour and second, with no additional information such as timezone or day of year. This form of timestamp is often ideal for print statements, logs and filenames.
    If the current number of seconds is not passed, then the current time is taken.
    The 'pretty' format is ideal for print statements, while the 'condensed' and 'dashed' formats are generally more appropriate for filenames.
    """
    if numSecs is None:
        numSecs = time.time()
    tuple     = time.localtime(numSecs)[:6]
    pretty    = '%4i-%02i-%02i %02i:%02i:%02i' % tuple
    condensed = '%4i%02i%02i%02i%02i%02i' % tuple
    dashed    = '%4i-%02i-%02i-%02i-%02i-%02i' % tuple
    return locals()


def uniqueId(forObject=None):
    """
    Generates an opaque, identifier string that is practically guaranteed to be unique.
    If an object is passed, then its id() is incorporated into the generation.
    Relies on md5 and returns a 32 character long string.
    """
    r = [time.time(), random.random(), os.times()]
    if forObject is not None:
        r.append(id(forObject))
    md5object = md5.new(str(r))
    try:
        return md5object.hexdigest()
    except AttributeError:
        # Older versions of Python didn't have hexdigest, so we'll do it manually
        hexdigest = []
        for char in md5object.digest():
            hexdigest.append('%02x' % ord(char))
        return string.join(hexdigest, '')


def valueForString(s):
    """
    For a given string, returns the most appropriate Pythonic value
    such as None, a long, an int, a list, etc. If none of those
    make sense, then returns the string as-is.

    "None", "True" and "False" are case-insensitive because there is
    already too much case sensitivity in computing, damn it!
    """
    if not s:
        return s
    try:
        return int(s)
    except ValueError:
        pass
    try:
        return long(s)
    except ValueError:
        pass
    try:
        return float(s)
    except ValueError:
        pass
    t = s.lower()
    if t=='none':
        return None
    if t=='true':
        return True
    if t=='false':
        return False
    if s[0] in '[({"\'':
        return eval(s)
    return s


### Deprecated

def Commas(number):
    print 'DEPRECATED: MiscUtils.Funcs.Commas() on 02/23/01 in ver 0.5. Use commas() instead.'
    return commas(number)

def CharWrap(s, width, hanging=0):
    print 'DEPRECATED: MiscUtils.Funcs.CharWrap() on 02/23/01 in ver 0.5. Use charWrap() instead.'
    return charWrap(s, width, hanging)